Yesterday, the house where the boys lived with their mother Claire Gilheaney Watson and father Robert O’Neill stood empty, with some of its windows whitewashed.

Claire, 32, and Robert, 39, are known to have family connections in England and Wales. The boys’ mother is also related to an extended traveller family, with ties to Irvine’s Redburn caravan site, according to local sources.

Chief Inspector Martyn Hopkins said: “North Ayrshire local authorities’ attempts to engage with the family prior to them going missing met with negative results, which has resulted in concerns being raised in respect of the children’s welfare.”

Neighbours said the “noisy” family hadn’t lived in the street long.

One woman said: “They caused some trouble but we didn’t know them well.”